The present invention relates to a warning device for tires and a pneumatic tire having a strain sensor thereof, and more particularly, to a tire warning device and a pneumatic tire which can make a contribution to safe traveling of a vehicle.
If traveling of a vehicle is kept without awareness of occurrence of tire breakdown during traveling, there is a risk that a serious traffic accident will be developed by burst of the tire. In particular, when traveling at high speed on an expressway or the like, a disastrous traffic accident will happen. Therefore, when tire breakdown occurs, it is very important to find it immediately for safe traveling.
Disclosed in Unexamined Japanese Patent Application Publication No. 3-262716 and Unexamined Japanese Utility Model Application Publication No. 63-189703 are conventional tire breakdown detection devices which use a temperature sensor, in which the temperature sensor senses the temperatures of the surface or cavity of a tire and tire breakdown is determined on the basis of the temperature changes. Occurrence of breakdown of a pneumatic tire significantly increases heat generated at a breakdown spot, and it is, therefore, very effective to find tire breakdown using the temperature sensor.
Such tire breakdown detection devices make a contribution to safe traveling of a vehicle. However, if it is possible to notify the driver of a state of the pneumatic tires of his vehicle before the pneumatic tire breaks down, a more contribution is made to his safe traveling.